Finding the Fourth Proportional to 1,009.38, 1,391.50 and 715.32

Step by Step Solution

1. Step 1: Write the proportion equation
   1,009.38 : 1,391.50 = 715.32 : x
2. Step 2: Convert to fraction form
   1,009.38/1,391.50 = 715.32/x
3. Step 3: Cross multiply
   1,009.38x = 1,391.50 × 715.32
4. Step 4: Simplify right side
   1,009.38x = 995,367.78
5. Step 5: Solve for x
   x = 995,367.78/1,009.38
6. Step 6: Final answer
   x = 986.12